Views:0 Author:Site Editor Publish Time: 2018-04-29 Origin:Site
Some people think that partial discharge is the main cause of fault, and if it is solved from partial discharge, the fault can be reduced. So, how to detect the medium voltage Y capacitors in operation?
1. The Y capacitor should operate at the rated voltage, and the long-term operating voltage should not exceed 1.1 times the rated voltage; it should be stopped immediately when it is found to exceed the rated voltage for a long period of 1.1 times.
2. Y capacitor should be carried out at rated current. The maximum current should not exceed 1.3 times the rated current. Once it is over, it should be stopped immediately.
3. Whether the Y capacitor housing is swelling, whether there is fuel injection and leakage.
4. Is there any discharge traces in the Y capacitor housing and whether there are discharge sounds or other abnormal noises inside it?
5. Y capacitance part is complete, lead to terminal, line porcelain sleeves and other loose, out of line porcelain sleeve cracks and oil leakage, porcelain glaze is not falling off, the coat surface paint is not falling off.
6. Y capacitance connection is hot.
Safety regulation Y capacitance for the general people may be a little strange, can not solve the safety regulation Y capacitance is what to use, in fact, the most important use of Y capacitance of the filter and coupling effect, the following will give you a specific introduction.
Coupling effect: in the process of transmitting and amplifying low-frequency signals, Y capacitance coupling is often adopted to prevent the interaction of static and operating points between the two circuits. In order to prevent the loss of the low frequency component of the signal in the middle of the signal is too large, the larger capacity of the electrolytic Y capacitor is generally adopted.
Filtering function: in the power circuit, the commutation circuit turns into a pulsating DC, and after the rectifying circuit, a large capacity electrolytic Y capacitor is connected, and the pulse DC voltage after rectification becomes relatively stable DC voltage by its charge discharge characteristics. In practice, in order to prevent the change of the power supply voltage of each part of the circuit due to the change of the load, the output end of the power supply and the input terminal of the load are generally connected with the electrolytic Y capacitance of tens to hundreds of Micromethods. Because the large capacity electrolytic Y capacitor generally has a certain inductance, the high frequency and pulse interference signals can not be effectively filtered, so a Y capacitor with a capacity of 0.001--0.l F is parallel to the two ends of the capacitor to filter the high frequency and pulse interference.
The importance of Y capacitance is like a rushing river flowing into a lake and letting it flow out. It is calm and soft. The Y capacitor should act as a lake to make the current cleaner and without clutter.